Explanation of Plates. 



Plate I. Skull of Pteranodon sp., one-fifth natural size. 



Plate II. Left front paddle of CHdastes velox Marsh, two-thirds 

 natural size. C, coracoid ; S, scapula; H, humerus; /, first digit; 

 V, fifth digit. 



Plate III. Left hind paddle of CHdastes velox Marsh, two-thirds 

 natural size. //, ilium; P, pubis; Is, ischium; F, femur; T, tibia; 

 Fb, fibula; /, first metatarsal. 



Plate IV. Right front paddle of CHdastes Westii Williston, one- 

 third natural size. S, scapula; C, coracoid ; H, humerus; R, radius; 

 U, ulna ; /, IV, first, fourth digits. 



Plate V. Right hind paddle of CHdastes Westii Williston, one- 

 half natural size. 



Plate VI. Eighteenth dorsal vertebra of CHdastes Westii Willis- 

 ton, natural size. Fig. i, centrum from behind; fig. 2, from below. 



Plate VII. Fig. i, Mic7'odon megalogaster Snow; fig. 2, Brachy- 

 opa cynops Snow; fig. 3, Syrphits ruficauda Snow; fig. 4, CalHcera 

 montensis Snow ; fig. 5, Tropidomyia hiniaculata Williston ; fig. 6, Rhing- 

 iopsis- rostrata Roeder ; fig. 7, Aneanthina hieroglyphica Wiedemann. 



Plate VIII. Melitera dentata. Adult, silken cocoon and outer 

 layer of dirt-masses held together by silken threads; larva (^shaded); 

 larva in outline showing position and number of tubercled hairs ; hind 

 wing of adult showing venation. 



